Exploitation of deep sea oil and gas reservoirs has increased demand for sealing systems used with deep sea equipment that are reliable, durable, and provide an airtight seal to prevent leakage of oil and gas. The sealing systems must be able to withstand the continual loads applied during operation. Due to the complex deep sea manmade structures used for deep sea installations, maintenance of the sealing systems in the deep sea equipment is extremely expensive or even impossible to perform. To minimize or eliminate the need for maintenance and repair of the sealing systems in the deep sea equipment, all critical components of the sealing systems must exhibit continual reliability and durability to fully comply with the stringent requirements of zero emissions to the environment.
Known metal valve stem seals and sealing systems for use with oil and gas drilling and related applications have been developed prior to the present invention. However, such seals and sealing systems have disadvantages such as insufficient and inadequate sealing capacity under high pressure conditions, premature wearing resulting in less durability and reliability, more frequent maintenance and repair, increased damage to the sealing surfaces, and often the use of more expensive equipment. In addition, many known valve stem seals and sealing systems incorporate plastic or elastomeric materials in the sealing construction. Such plastic or elastomeric materials are less advantageous than metals when used in deep sea oil and gas drilling, due to the propensity for the plastic or elastomeric materials to wear out more easily and/or explode under high pressure conditions.
Accordingly, there is a need for a new and improved metal valve stem seal and sealing system that overcomes the problems associated with known valve stem seals and sealing systems.